Substrate processing method, semiconductor device manufacturing method, substrate processing apparatus, and recording medium

Abstract

A process includes: (a) supplying a film formation gas into a processing vessel in which a substrate is housed to form a film on the substrate; (b) supplying a fluorine-containing gas into the processing vessel in which the substrate is not housed to remove a deposit including the film adhered to the inside of the processing vessel; (c) supplying a pre-coating gas into the processing vessel in which the deposit is removed after the substrate is not housed to form a pre-coating film in the processing vessel; and (d) supplying a film formation gas into the processing vessel in which the pre-coating film is formed after the substrate is housed to form a film on the substrate, and in (c), a film thickness distribution of the pre-coating film is adjusted in correspondence with a distribution of a residual fluorine concentration in the processing vessel.

Description

Technical Field

[0001] This disclosure relates to a substrate processing method, a method for manufacturing a semiconductor device, a substrate processing apparatus, and a recording medium. Background Technology

[0002] As a step in the manufacturing process of a semiconductor device, sometimes after a film-forming process is performed to form a film on a substrate housed in a processing container, a cleaning process is performed inside the processing container (for example, see Patent Document 1).

[0003] Patent Document 1: Japanese Patent Application Publication No. 2012-216696 Summary of the Invention

[0004] The problem that the invention aims to solve

[0005] However, if cleaning is performed, the film formation rate decreases during the subsequent film formation process, and sometimes a thinning of the film formed on the substrate occurs within the processing container (film drop). The purpose of this disclosure is to suppress film drop within the processing container after cleaning.

[0006] Methods for solving problems

[0007] According to one aspect of this disclosure, a technique is provided comprising the following steps: (a) supplying a film-forming gas into a processing container containing a substrate to form a film on the substrate; (b) supplying a fluorine-containing gas into the processing container not containing the substrate to remove deposits containing the film adhering to the processing container; (c) supplying a precoat gas into the processing container after the deposits have been removed to form a precoat film in the processing container; and (d) supplying a film-forming gas into the processing container containing the substrate after the precoat film has been formed to form a film on the substrate, wherein in (c), the film thickness distribution of the precoat film is adjusted in accordance with the distribution of residual fluorine concentration in the processing container.

[0008] Invention Effects

[0009] According to this disclosure, it is possible to suppress the reduction in film thickness within the cleaning process container. Attached Figure Description

[0010] Figure 1 This is a schematic structural diagram of a vertical processing furnace of a substrate processing apparatus preferred in one aspect of the present disclosure, and is a diagram showing the processing furnace 202 portion in a longitudinal sectional view.

[0011] Figure 2This is a schematic structural diagram of the controller 121 of a substrate processing apparatus preferably used in one aspect of the present disclosure, and is a block diagram showing the control system of the controller 121.

[0012] Figure 3 This is a schematic structural diagram of a vertical processing furnace of a substrate processing apparatus preferred in one aspect of the present disclosure, and is a diagram showing the processing container portion in a longitudinal sectional view.

[0013] Figure 4 This is a flowchart of one step in the manufacturing process of a semiconductor device carried out in one aspect of this disclosure. Detailed Implementation

[0014] <One method of this disclosure>

[0015] The following is mainly based on Figure 1 One aspect of this disclosure will be described. Furthermore, the accompanying drawings used in the following description are schematic, and the dimensional relationships and ratios of the elements in the drawings may not necessarily correspond to reality. Additionally, the dimensional relationships and ratios of the elements may not be consistent between different drawings.

[0016] (1) Structure of the substrate processing device

[0017] like Figure 1 As shown, the processing furnace 202 has a heater 206 that serves as a temperature adjustment unit (heating unit). The heater 206 is cylindrical and is vertically mounted by means of a heater base 251, which serves as a retaining plate. The heater 206 is configured to be divided into five regions from top to bottom: U (Upper), CU (Center Upper), C (Center), CL (Center Lower), and L (Lower), allowing for independent temperature control of each region. The heater 206 also functions as an activation mechanism (excitation unit) that uses heat to activate (excite) the gas. Insulating material 208 is provided around and above the heater 206 to cover it.

[0018] Inside the heater 206, a processing tube 203, serving as a reaction tube, is arranged concentrically with the heater 206. The processing tube 203 includes an inner tube 204 serving as an internal reaction tube and an outer tube 205 serving as an external reaction tube. The inner tube 204 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed into a cylindrical shape with openings at the top and bottom. A processing chamber 201 for processing the wafer 200, which serves as a substrate, is formed in the hollow portion of the inner tube 204. The processing chamber 201 is configured to accommodate the wafer boat 217, which will be described later. The outer tube 205 is made of a heat-resistant material such as quartz or SiC and is formed into a cylindrical shape with an inner diameter larger than the outer diameter of the inner tube 204, closed at the top and open at the bottom, and is arranged concentrically with the inner tube 204.

[0019] Below the outer tube 205, a manifold 209 is arranged concentrically with the outer tube 205. The manifold 209 is made of a metal material such as stainless steel (SUS) and is formed into a cylindrical shape with open top and bottom. The manifold 209 is configured to engage with and support the inner tube 204 and the outer tube 205. An O-ring 220a as a sealing component is provided between the manifold 209 and the outer tube 205. The processing tube 203 is installed vertically in the same manner as the heater 206. The processing container (reaction vessel) is mainly composed of the processing tube 203 and the manifold 209. The space inside the processing container composed of the processing tube 203 and the manifold 209 can also be called the processing chamber 201.

[0020] Additionally, the area within the processing container corresponding to region U is sometimes referred to as the upper region. Sometimes, the area within the processing container corresponding to region CU is also considered to be included in the upper region. Additionally, the area within the processing container corresponding to region L is sometimes referred to as the lower region. Sometimes, the area within the processing container located below region L, such as manifold 209, the heat insulation plate 216 (described later), and the sealing cap 219, is also considered to be included in the lower region. Sometimes, the area within the processing container corresponding to region CL is also considered to be included in the lower region. Additionally, the area within the processing container corresponding to region C is sometimes referred to as the central region. Sometimes, the area within the processing container corresponding to at least one of regions CU and CL is also considered to be included in the central region.

[0021] Nozzles 230a and 230b, which serve as gas inlets, are connected to manifold 209 in a manner that allows them to communicate with the interior of processing chamber 201. Gas supply pipes 232a and 232b are connected to nozzles 230a and 230b, respectively.

[0022] On the gas supply pipes 232a and 232b, starting from the upstream side of the airflow, gas supply sources 271 and 272, valves 262a and 262b as on / off valves, MFC (mass flow controller) 241a and 241b as flow controllers, and valves 261a and 261b are respectively arranged in sequence.

[0023] Gas supply pipes 232c and 232d are connected downstream of valves 261a and 262b in gas supply pipes 232a and 232b, respectively. Gas supply pipes 232c and 232d are provided sequentially from upstream of the gas flow, including gas supply source 273, valves 262c and 262d, MFC 241c and 241d, and valves 261c and 261d.

[0024] Gas supply pipes 232e and 232f are connected downstream of valves 261a and 261b of gas supply pipes 232a and 232b, respectively, and downstream of the connection points with gas supply pipes 232c and 232d. Gas supply pipes 232e and 232f are sequentially provided with a gas supply source 274, valves 262e and 262f, MFC 241e and 241f, and valves 261e and 261f, respectively, starting from the upstream side of the gas flow.

[0025] Gas supply pipes 232a~232f are made of metal materials such as SUS.

[0026] Raw material gas is supplied to the processing chamber 201 from gas supply pipe 232a via gas supply source 271, valve 262a, MFC 241a, and valve 261a. In this specification, for convenience, the raw material gas is sometimes referred to as raw material.

[0027] The reaction gas is supplied to the processing chamber 201 through the gas supply pipe 232b, gas supply source 272, valve 262b, MFC 241b, and valve 261b. In this specification, for convenience, the reaction gas is sometimes referred to as the reaction body.

[0028] Inert gas is supplied to the processing chamber 201 through gas supply pipes 232c and 232d via gas supply source 273, valves 262c and 262d, MFC 241c and 241d, and valves 261c and 261d. The inert gas serves as a purging gas, carrier gas, and dilution gas.

[0029] Fluorine (F) gas is supplied to the processing chamber 201 from gas supply pipes 232e and 232f via gas supply source 274, valves 262e and 262f, MFC 241e and 241f, and valves 261e and 261f. For convenience, the F-containing gas is sometimes referred to as clean gas in this specification.

[0030] The feed gas supply system mainly consists of gas supply pipes 232a, MFC 241a, and valves 261a and 262a. Gas supply source 271 can also be included in the feed gas supply system. The reaction gas supply system mainly consists of gas supply pipes 232b, MFC 241b, and valves 261b and 262b. Gas supply source 272 can also be included in the reaction gas supply system. The inert gas supply system mainly consists of gas supply pipes 232c and 232d, MFC 241c and 241d, and valves 261c, 262c, 261d, and 262d. Gas supply source 273 can also be included in the inert gas supply system. The fluorine-containing gas supply system mainly consists of gas supply pipes 232e and 232f, MFC 241e and 241f, and valves 261e, 262e, 261f, and 262f. Gas supply source 274 can also be included in the fluorine-containing gas supply system.

[0031] Furthermore, the raw material gas and the reactant gas, or both, are referred to as film-forming gases, and the raw material gas supply system and the reactant gas supply system, or both, are referred to as film-forming gas supply systems. Additionally, when the film-forming gas is used as the pre-coating gas described later, the film-forming gas supply system is also referred to as a pre-coating gas supply system. Furthermore, the F-containing gas supply system is also referred to as a clean gas supply system.

[0032] Any or all of the aforementioned gas supply systems can be configured as an integrated gas supply system 248 consisting of integrated valves 261a-261f, 262a-262f, and MFCs 241a-241f. The integrated gas supply system 248 is configured to connect to gas supply pipes 232a-232f, and the controller 121 (described later) controls the supply of various gases to the gas supply pipes 232a-232f, including the opening and closing of valves 261a-261f and 262a-262f, and flow adjustment using MFCs 241a-241f. The integrated gas supply system 248 can be configured as a single or segmented integrated unit, allowing for assembly and disassembly of the integrated units relative to the gas supply pipes 232a-232f, and enabling maintenance, replacement, and addition of the integrated gas supply system 248 on a unit-by-unit basis.

[0033] An exhaust pipe 231 for venting the atmosphere inside the processing chamber 201 is provided in the manifold 209. The exhaust pipe 231 is made of a metal material such as SUS. The exhaust pipe 231 is located at the lower end of the cylindrical space 250 formed by the gap between the inner pipe 204 and the outer pipe 205, and communicates with the cylindrical space 250. A vacuum pump 246, which is a vacuum venting device, is connected to the exhaust pipe 231 via a pressure sensor 245, which is a pressure detector (pressure detection unit) for detecting the pressure inside the processing chamber 201, and an APC (AutoPressure Controller) valve 242, which is a pressure regulator (pressure adjustment unit). The APC valve 242 is configured such that by opening and closing the valve while the vacuum pump 246 is operating, vacuum venting and vacuum venting stop can be performed inside the processing chamber 201. Furthermore, by adjusting the valve opening based on the pressure information detected by the pressure sensor 245 while the vacuum pump 246 is operating, the pressure inside the processing chamber 201 can be adjusted. The exhaust system mainly consists of exhaust pipe 231, APC valve 242, and pressure sensor 245. Alternatively, a vacuum pump 246 could be included in the exhaust system.

[0034] The lower opening of the manifold 209 is used as a substrate transfer port 209a for transporting the wafer 200 inside and outside the processing container, i.e., inside and outside the processing chamber 201. Below the manifold 209 is a sealing cover 219, which acts as a furnace opening cover, capable of hermetically sealing the substrate transfer port 209a when the wafer boat 217 (described later) is placed inside the processing chamber 201. The sealing cover 219 is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220b, serving as a sealing member, is provided on the upper surface of the sealing cover 219 and abuts against the lower end of the manifold 209. Below the sealing cover 219 is a rotation mechanism 254 for rotating the wafer boat 217. The rotation shaft 255 of the rotation mechanism 254, made of a metal material such as SUS, passes through the sealing cover 219 and is connected to the wafer boat 217. The rotation mechanism 254 is configured to rotate the wafer 200 by rotating the wafer boat 217. The sealing cover 219 is configured to be raised and lowered vertically by a wafer boat lift 115, which is provided outside the processing tube 203 as a lifting mechanism. The wafer boat lift 115 is configured as a conveying device (conveying mechanism) that moves the wafer 200 into and out of the processing chamber 201 by raising and lowering the sealing cover 219.

[0035] Below the manifold 209 is a gate 219a, which acts as a furnace opening cover, capable of hermetically sealing the substrate transport port 209a when the sealing cover 219 is lowered to remove the wafer boat 217 from the processing chamber 201. The gate 219a is made of a metal material such as SUS and is formed in a disc shape. The gate 219a is configured to hermetically seal the lower end of the manifold 209 by lifting and rotating. An O-ring 220c, serving as a sealing member, is provided on the upper surface of the gate 219a, abutting against the lower end of the manifold 209. The opening and closing actions (lifting, rotating, etc.) of the gate 219a are controlled by… Figure 2 The gate opening and closing mechanism shown is controlled by 115s.

[0036] The wafer boat 217, serving as a substrate holder, is configured to support multiple wafers 200, for example, 25 to 200 wafers 200 arranged horizontally and aligned with each other in a vertical direction, i.e., arranged at intervals. The wafer boat 217 is made of a heat-resistant material such as quartz or SiC. The wafer boat 217 is also configured to support multiple heat insulation plates 216, for example, 2 to 20, arranged horizontally and aligned with each other in a vertical direction in a region lower than the area where the wafers 200 are arranged, i.e., arranged at intervals. The heat insulation plates 216 are made of heat-resistant materials such as quartz or SiC. By providing the heat insulation plates 216 lower than the area where the wafers 200 are arranged, heat from the heater 206 is less likely to be transferred to the manifold 209 side.

[0037] A temperature sensor 263, serving as a temperature detector, is installed inside the processing tube 203. Based on the temperature information detected by the temperature sensor 263, the energization of each of the five zones (L, CL, C, CU, U) of the heater 206 is independently adjusted, thereby achieving the desired temperature distribution within the processing chamber 201. The temperature sensor 263 is installed along the inner wall of the processing tube 203.

[0038] like Figure 2 As shown, the controller 121, serving as the control unit (control unit), is configured as a computer equipped with a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. The RAM 121b, storage device 121c, and I / O port 121d are configured to exchange data with the CPU 121a via an internal bus 121e. The controller 121 is configured to connect to an input / output device 122, such as a touch panel, and an external storage device 123.

[0039] The storage device 121c is composed of, for example, flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), etc. The storage device 121c stores, in a readable manner, a control program for controlling the operation of the substrate processing apparatus, a process flow describing the steps and conditions of the substrate processing described later, a cleaning process describing the steps and conditions of the cleaning process described later, and a pre-coating process describing the steps and conditions of the pre-coating process described later. The process flow is a combination of methods that enable the controller 121 to execute each step in the substrate processing described later to obtain a predetermined result, and functions as a program. The cleaning process is a combination of methods that enable the controller 121 to execute each step in the cleaning process described later to obtain a predetermined result, and functions as a program. The pre-coating process is a combination of methods that enable the controller 121 to execute each step in the pre-coating process described later to obtain a predetermined result, and functions as a program. Hereinafter, the process flow, cleaning process, pre-coating process, control program, etc., will be collectively referred to as a program. In addition, the process, cleaning process, and pre-coating process are simply referred to as the process. When the term "program" is used in this specification, sometimes only the process is included, sometimes only the control program is included, or sometimes both are included. RAM121b is configured as a storage area (working area) for temporarily holding programs, data, etc. read by CPU121a.

[0040] I / O port 121d is connected to the aforementioned MFC241a~241f, valves 261a~261f, 262a~262f, pressure sensor 245, APC valve 242, vacuum pump 246, temperature sensor 263, heater 206, rotating mechanism 254, wafer boat lifting mechanism 115, gate opening and closing mechanism 115s, etc.

[0041] CPU 121a is configured to read and execute control programs from storage device 121c, and to read process data from storage device 121c based on input commands from input / output device 122. CPU 121a is configured to control, according to the read process data, the following actions: flow rate adjustment of various gases by MFCs 241a-241f; opening and closing of valves 261a-261f, 262a-262f; opening and closing of APC valve 242 and pressure adjustment of APC valve 242 based on pressure sensor 245; starting and stopping of vacuum pump 246; temperature adjustment of heater 206 based on temperature sensor 263; rotation and speed adjustment of wafer boat 217 by rotation mechanism 254; lifting and lowering of wafer boat 217 by wafer boat lift 115; and opening and closing of gate 219a by gate opening and closing mechanism 115s.

[0042] The controller 121 is configured to install the aforementioned program stored in the external storage device 123 onto a computer. The external storage device 123 includes, for example, a hard disk such as an HDD, an optical disk such as a CD, an optical disk such as an MO, a USB memory, and a semiconductor memory such as an SSD. The storage device 121c and the external storage device 123 constitute a computer-readable recording medium. Hereinafter, they will also be collectively referred to as recording media. When the term "recording medium" is used in this specification, sometimes only the storage device 121c is included, sometimes only the external storage device 123 is included, or sometimes both are included. Furthermore, providing the program to the computer may also be done without using the external storage device 123, but using communication means such as the Internet or a dedicated line.

[0043] (2) Film-forming treatment (before cleaning)

[0044] The aforementioned substrate processing apparatus, as a step in the manufacturing process of semiconductor devices, primarily uses... Figure 4 An example of the processing sequence for the wafer 200, which serves as a substrate, is described below, specifically an example of the film formation sequence for forming a film on the wafer 200. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by the controller 121.

[0045] In this film formation sequence, film-forming gas is supplied to the processing container containing the wafer 200 to form a film on the wafer 200.

[0046] The following describes examples of nitride films formed as films. Here, nitride films include not only silicon nitride films (SiN films), but also nitride films containing carbon (C), oxygen (O), boron (B), etc. That is, nitride films include silicon nitride films (SiN films), silicon carbonitride films (SiCN films), silicon oxynitride films (SiON films), silicon carbonitride films (SiOCN films), silicon boron oxynitride films (SiBCN films), silicon boron nitride films (SiBN films), borate carbonitride films (SiBOCN films), and silicon borate nitride films (SiBON films), etc. The following describes examples of SiN films formed as nitride films.

[0047] Furthermore, the following describes an example in which the film-forming process includes a predetermined number of cycles (m times, where m is an integer greater than or equal to 1) of steps comprising supplying a raw material gas (as a film-forming gas) to wafer 200 and a reactant gas (as a film-forming gas) to wafer 200. Moreover, the steps of supplying the raw material gas and the steps of supplying the reactant gas can be performed alternately, i.e., not simultaneously; alternatively, these steps can be performed simultaneously. In this specification, for convenience, the processing order of not performing these steps simultaneously and the processing order of performing these steps simultaneously are sometimes shown below. The same reference numerals are also used in the following descriptions of other methods, variations, etc. Hereinafter, in this method, an example of performing these steps simultaneously, i.e., an example of the latter processing order, will be described as an example.

[0048] (Raw material gas → Reactant gas) × m

[0049] (raw material gas + reactant gas) × m

[0050] In this specification, the term "wafer" sometimes refers to the wafer itself, and sometimes to a laminate of the wafer and a predetermined layer or film formed on its surface. In this specification, the term "surface of the wafer" sometimes refers to the surface of the wafer itself, and sometimes to the surface of a predetermined layer or the like formed on the wafer. In this specification, when described as "forming a predetermined layer on the wafer," it sometimes means forming the predetermined layer directly on the surface of the wafer itself, and sometimes it means forming the predetermined layer on a layer or the like formed on the wafer. The use of the term "substrate" in this specification is synonymous with the use of the term "wafer."

[0051] (Wafer loading)

[0052] Multiple wafers 200 are loaded into wafer boat 217 (wafer loading). Then, the gate 219a is moved by the gate opening and closing mechanism 115s, so that the lower end opening of the manifold 209 is opened (gate opening).

[0053] (Carried on a wafer boat)

[0054] After that, as Figure 1 As shown, a wafer boat 217 supporting multiple wafers 200 is lifted by a wafer boat lift 115 and moved into the processing chamber 201 (wafer boat loading). In this state, the sealing cap 219 seals the lower end of the manifold 209 via an O-ring 220b.

[0055] (Pressure adjustment and temperature adjustment)

[0056] After the wafer boat is loaded, vacuum pump 246 is used to vent the vacuum (pressure reduction venting) to bring the processing chamber 201, i.e., the space where the wafer 200 is located, to the desired pressure (vacuum level). At this time, the pressure in the processing chamber 201 is measured by pressure sensor 245, and the APC valve 242 is controlled by feedback (pressure adjustment) based on the measured pressure information. In addition, heater 206 is used to heat the wafer 200 in the processing chamber 201 to the desired processing temperature. At this time, in order to achieve the desired temperature distribution in the processing chamber 201, the energization of heater 206, i.e., the energization of each of the five regions (L, CL, C, CU, U) of heater 206, is independently controlled by feedback (temperature adjustment) based on the temperature information detected by temperature sensor 263. In addition, the rotation of wafer 200 by rotation mechanism 254 begins. Venting in the processing chamber 201, heating of wafer 200, and rotation are all carried out continuously at least until the processing of wafer 200 is completed.

[0057] (Film-forming treatment)

[0058] Then, perform steps 1 and 2 in sequence.

[0059] [Step 1]

[0060] In step 1, raw material gas and reaction gas are simultaneously supplied to the wafer 200 in the processing chamber 201 as film-forming gas.

[0061] Specifically, valves 261a, 262a, 261b, and 262b are opened to allow the raw material gas and reactant gas to flow within gas supply pipes 232a and 232b, respectively. The flow rates of the raw material gas and reactant gas are regulated by MFCs 241a and 241b, and supplied to the processing chamber 201 via nozzles 230a and 230b. The raw material gas and reactant gas supplied to the processing chamber 201 rise within it, flow out from the upper opening of the inner pipe 204 into the cylindrical space 250, and after flowing down into the cylindrical space 250, are discharged from the exhaust pipe 231. During this process, the raw material gas and reactant gas are mixed, and the mixed raw material gas and reactant gas (film-forming gas) are supplied to the wafer 200. At this time, valves 261c, 262c, 261d, and 262d can also be opened to supply inert gas to the processing chamber 201 via nozzles 230a and 230b, respectively.

[0062] As a processing condition in this step, the following examples are provided:

[0063] Processing temperature: 600~850℃, preferably 650~800℃

[0064] Processing pressure: 1~2666Pa, preferably 13~1333Pa

[0065] Raw material gas supply flow rate: 0.01~2 slm, preferably 0.05~0.2 slm

[0066] Reactant gas supply flow rate: 0.1~10 slm, preferably 0.5~2 slm

[0067] Inert gas supply flow rate (per gas supply pipe): 0~5slm

[0068] Gas supply time: 1~600 minutes, preferably 1~60 minutes

[0069] In this specification, the expression of a numerical range such as "1~2666 Pa" means that the lower and upper limits are included within that range. Therefore, for example, "1~2666 Pa" means "above 1 Pa and below 2666 Pa". The same applies to other numerical ranges. Furthermore, the processing temperature in this specification refers to the temperature of the wafer 200 or the temperature inside the processing chamber 201, and the processing pressure refers to the pressure inside the processing chamber 201. Additionally, the gas supply flow rate of 0 slm indicates that the gas is not supplied. These same principles apply in the following descriptions.

[0070] Using chlorosilane gases as raw material gases, for example, as described later, and using nitriding gases as reaction gases, for example, as described later, step 1 is performed under the above-described processing conditions to form a layer containing Si and N, namely a silicon nitride layer (SiN layer), on the outermost surface of the wafer 200, which serves as a substrate, by thermal CVD reaction.

[0071] As a feedstock gas, for example, a silane gas containing silicon (Si), which is the main element constituting the film formed on wafer 200, can be used. As a silane gas, for example, a gas containing Si and a halogen, i.e., a halosilane gas, can be used. Halogens include chlorine (Cl), fluorine (F), bromine (Br), iodine (I), etc. As a halosilane gas, for example, a chlorosilane gas containing Si and Cl can be used.

[0072] As feedstock gases, chlorosilane gases such as monochlorosilane (SiH3Cl, abbreviated as MCS), dichlorosilane (SiH2Cl2, abbreviated as DCS), trichlorosilane (SiHCl3, abbreviated as TCS), tetrachlorosilane (SiCl4, abbreviated as STC), hexachlorodisilane (Si2Cl6, abbreviated as HCDS), and octachlorotrisilane (Si3Cl8, abbreviated as OCTS) can be used. One or more of these gases can be used as feedstock gases.

[0073] In addition to chlorosilane gases, other raw material gases such as tetrafluorosilane (SiF4) and difluorosilane (SiH2F2), bromosilane (SiBr4) and dibromosilane (SiH2Br2), and iodosilane (SiI4) and diiodosilane (SiH2I2) can also be used as raw material gases. More than one of these can be used.

[0074] In addition to the above, gases containing Si and amino groups, i.e., aminosilane gases, can also be used as feedstock gases. An amino group refers to a monovalent functional group obtained by removing H from ammonia, primary amines, or secondary amines, and can be represented as -NH2, -NHR, or -NR2. Furthermore, R represents an alkyl group, and the two Rs in -NR2 can be the same or different.

[0075] As feedstock gases, for example, tetra(dimethylamino)silane (Si[N(CH3)2]4, abbreviated as 4DMAS) gas, tri(dimethylamino)silane (Si[N(CH3)2]3H, abbreviated as 3DMAS) gas, bis(diethylamino)silane (Si[N(C2H5)2]2H2, abbreviated as BDEAS) gas, bis(tert-butylamino)silane (SiH2[NH(C4H9)]2, abbreviated as BTBAS) gas, and diisopropylamino)silane (SiH3[N(C3H3[N(C3H7)2], abbreviated as DIPAS) gas, etc., can be used. One or more of these can be used as feedstock gases.

[0076] As the reactant gas, a nitrogen- (N) and hydrogen- (H) gas can be used as a nitriding gas (nitriding agent). The N- and H-containing gas is both a N-containing gas and a H-containing gas. The N- and H-containing gas preferably has NH bonds.

[0077] For example, hydrogen nitride gases such as ammonia (NH3), diazoxide (N2H2), hydrazine (N2H4), and N3H8 can be used as reactants. More than one of these gases can be used as reactants.

[0078] In addition to nitrogen (N), carbon (C), and hydrogen (H) gases, gases containing N, C, and H can also be used as reactant gases. For example, amine gases and organic hydrazine gases can be used as N, C, and H gases. A gas containing N, C, and H is a gas containing N, a gas containing C, a gas containing H, and a gas containing both N and C.

[0079] Examples of reactant gases include ethylamine gases such as monoethylamine (C2H5NH2, abbreviated as MEA), diethylamine ((C2H5)2NH, abbreviated as DEA), and triethylamine ((C2H5)3N, abbreviated as TEA); methylamine gases such as monomethylamine (CH3NH2, abbreviated as MMA), dimethylamine ((CH3)2NH, abbreviated as DMA), and trimethylamine ((CH3)3N, abbreviated as TMA); and organohydrazine gases such as monomethylhydrazine ((CH3)HN2H2, abbreviated as MMH), dimethylhydrazine ((CH3)2N2(CH2, abbreviated as DMH2), and trimethylhydrazine ((CH3)2N2(CH3)H, abbreviated as TMH). One or more of these gases may be used as reactant gases.

[0080] As inert gases, rare gases such as nitrogen (N2), argon (Ar), helium (He), neon (Ne), and xenon (Xe) can be used. More than one of these gases can be used as an inert gas. This also applies to the steps described later.

[0081] [Step 2]

[0082] After step 1 is completed, close valves 261a, 262a, 261b, and 262b to stop the supply of raw material gas and reaction gas to the processing chamber 201. Then, perform vacuum venting in the processing chamber 201 to remove any remaining gases (purging). At this time, valves 261c, 262c, 261d, and 262d can also be opened to supply purging gas to the processing chamber 201, which is then exhausted through exhaust pipe 231.

[0083] The following conditions are cited as processing conditions in this step:

[0084] Processing pressure: 1~20Pa, preferably 1~10Pa

[0085] Purge gas supply flow rate: 0~10 slm, preferably 0~5 slm

[0086] Purging time: 1~60 minutes, preferably 1~10 minutes

[0087] Other processing conditions can be the same as those in step 1. Furthermore, the aforementioned reaction gas or inert gas can be used as the purging gas.

[0088] [Number of scheduled implementations]

[0089] By performing steps 1 and 2 of the above process asynchronously a predetermined number of times (m times, where m is an integer greater than or equal to 1), a silicon nitride film (SiN film) of a desired thickness can be formed on the surface of wafer 200. It is preferable to repeat the above process multiple times. That is, it is preferable to make the thickness of the SiN layer formed in each cycle thinner than the desired film thickness, and to repeat the above process multiple times until the thickness of the SiN film formed by stacking SiN layers reaches the desired thickness. Furthermore, when using a gas containing N, C, and H as the reactant gas, a silicon carbonitride film (SiCN film) can also be formed on the surface of wafer 200.

[0090] (Post-purge and atmospheric pressure recovery)

[0091] After the film formation on wafer 200 is completed, inert gas is supplied into processing chamber 201 through nozzles 230a and 230b as purging gas, and exhaust is performed through exhaust pipe 231. This purging process removes residual gases and byproducts from processing chamber 201 (post-purging). Afterwards, the atmosphere in processing chamber 201 is replaced with inert gas (inert gas replacement), and the pressure inside processing chamber 201 is restored to atmospheric pressure (atmospheric pressure restoration).

[0092] (Unloading of wafer boat)

[0093] Next, the sealing cap 219 is lowered by the wafer boat lift 115, opening the lower end of the manifold 209. Then, the processed wafer 200, supported by the wafer boat 217, is moved out of the processing tube 203 from the lower end opening of the manifold 209 (wafer boat unloading). After the wafer boat is unloaded, the gate 219a is moved, and the lower end opening of the manifold 209 is sealed by the gate 219a via the O-ring 220c (gate closing).

[0094] (Wafer Release)

[0095] After the wafer boat is unloaded, i.e., after the gate is closed, the processed wafer 200 is cooled to a predetermined temperature at which it can be removed while supported by the wafer boat 217 (wafer cooling). After the wafer is cooled, the processed wafer 200, cooled to the predetermined temperature at which it can be removed, is removed from the wafer boat 217 (wafer release).

[0096] (3) Cleaning treatment

[0097] If the above-described film-forming process is performed, film-containing deposits adhere to the surfaces of components within the processing container, such as the inner wall of the processing tube 203 and the surface of the wafer boat 217. Therefore, after performing the above-described film-forming process a predetermined number of times (at least once), an F-containing gas is supplied to the processing container that does not contain the wafer 200 to remove the film-containing deposits adhering to the processing container. Hereinafter, the following will primarily use... Figure 4 An example of the cleaning process sequence, i.e., a cleaning sequence example, will be described below. In the following description, the operation of each part constituting the substrate processing apparatus is also controlled by the controller 121.

[0098] (Empty crystal wafer boat)

[0099] The gate 219a is moved by the gate opening and closing mechanism 115s, opening the lower end of the manifold 209 (gate opening). Then, an empty wafer boat 217 with a film-containing deposit on its surface, i.e., a wafer boat 217 not holding the wafer 200, is lifted by the wafer boat lift 115 and moved into the processing chamber 201 with the film-containing deposit on its surface (empty wafer boat loading). In this state, the sealing cap 219 seals the lower end of the manifold 209 via the O-ring 220b. Furthermore, the empty wafer boat 217 does not hold the wafer 200, but may, for example, hold the heat insulation plate 216, i.e., hold the heat insulation plate 216.

[0100] (Pressure adjustment and temperature adjustment)

[0101] After the empty wafer boat is loaded, vacuum pump 246 is used to perform vacuum venting (pressure reduction venting) to bring the processing chamber 201 to the desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by pressure sensor 245, and the APC valve 242 is controlled based on this measured pressure information (pressure adjustment). Additionally, heating is performed by heater 206 to bring the processing chamber 201 to the desired processing temperature. To achieve the desired temperature distribution inside the processing chamber 201, feedback control (temperature adjustment) is performed independently on the energization of heater 206, specifically on each of the five regions (L, CL, C, CU, U) of heater 206, based on temperature information detected by temperature sensor 263. Furthermore, the empty wafer boat 217 is rotated using rotation mechanism 254. The operation of vacuum pump 246, heating inside processing chamber 201, and rotation of wafer boat 217 all continue at least until the cleaning process is completed. Alternatively, wafer boat 217 may not rotate.

[0102] (Including F gas supply)

[0103] Then, F-containing gas is supplied to the processing chamber 201 that does not contain the wafer 200.

[0104] Specifically, valves 261e, 262e, 261f, and 262f are opened to allow F-containing gas to flow from gas supply source 274 into gas supply pipes 232e and 232f. The flow rate of the F-containing gas is adjusted by MFCs 241e and 241f, and it is supplied to the processing chamber 201 through nozzles 230a and 230b, respectively. The F-containing gas supplied to the processing chamber 201 rises within the chamber and flows out from the upper opening of the inner pipe 204 into the cylindrical space 250. After flowing down in the cylindrical space 250, it is discharged from the exhaust pipe 231. During this process, F-containing gas is supplied to the surface of the components inside the processing container (F-containing gas supply). At this time, valves 261c, 262c, 261d, and 262d can also be opened to supply inert gas into the processing chamber 201 through nozzles 230a and 230b, respectively.

[0105] As a processing condition in this step, the following examples are provided:

[0106] Processing temperature: 300~500℃, preferably 350~450℃

[0107] Processing pressure: 1~60000Pa, preferably 5000~20000Pa

[0108] F-containing gas supply flow rate: 1~20 slm, preferably 1~10 slm

[0109] Inert gas supply flow rate (per gas supply pipe): 0~5slm

[0110] Gas supply time: 1~600 minutes, preferably 1~80 minutes

[0111] Using the gas described later as an F-containing gas, the F-containing gas is supplied under the above-described processing conditions, thereby enabling the removal of film-containing deposits adhering to the processing container through a thermochemical reaction (etching reaction) with the F-containing gas.

[0112] As the fluorine-containing gas, fluorine (F2) gas, chlorine trifluoride (ClF3) gas, chlorine monofluoride (ClF) gas, nitrogen trifluoride (NF3) gas, hydrogen fluoride (HF) gas, nitrosyl fluoride (FNO) gas, F2 gas + nitrogen oxide (NO) gas, ClF3 gas + NO gas, ClF gas + NO gas, NF3 gas + NO gas, and other fluorine (F)-containing gases can be used. More than one of these can be used as the fluorine-containing gas. Furthermore, in this specification, the description of "NF3 gas + NO gas" refers to a mixture of NF3 gas and NO gas. When supplying a mixed gas, the two gases can be mixed (premixed) in the supply pipe before being supplied to the processing chamber 201, or the two gases can be supplied to the processing chamber 201 separately from different supply pipes and mixed (postmixed) in the processing chamber 201.

[0113] (After purging)

[0114] After the removal of the film-containing deposits adhering to the treatment container is completed, valves 261e, 262e, 261f, and 262f are closed to stop the supply of F-containing gas to the treatment chamber 201. Then, inert gas is supplied to the treatment chamber 201 through nozzles 230a and 230b, and exhaust is performed through exhaust pipe 231. As a result, the treatment chamber 201 is purged, and the gas, by-products, etc. remaining in the treatment chamber 201 are removed (post-purging).

[0115] (4) Pre-coating treatment

[0116] As described above, in the cleaning process, after the removal of the film-containing deposits adhering to the processing container is completed, a post-purging process is performed to remove F-containing gases from the processing container. However, even after post-purging, there is a situation where F remains in the processing container at a predetermined concentration immediately after the cleaning process. The F remaining in the processing container (hereinafter, residual F component) sometimes consumes the film-forming gas in the subsequent film-forming process, reducing the amount of film-forming gas supplied to the wafer 200. That is, the residual F component in the processing container sometimes increases the amount of film-forming gas consumed without contributing to film formation, thus reducing the film formation rate. In other words, the residual F component in the processing container may become a major cause of thinning of the film formed on the wafer 200 in the subsequent film-forming process, i.e., a reduction in film thickness.

[0117] Therefore, in this method, after the cleaning process, the following process is performed: a pre-coating gas is supplied to the processing container after the removal of the deposits of the unaccounted wafer 200, and a pre-coating film is formed inside the processing container. By performing this pre-coating process, the residual F component inside the processing container can react with the pre-coating gas, removing the residual F component from the processing container and reducing the concentration of residual F in the processing container (hereinafter referred to as residual F concentration). As a result, in the subsequent film deposition process, the reduction in film thickness can be suppressed.

[0118] However, the inventors of this application discovered that even after the aforementioned pre-coating treatment, depending on the processing conditions, film thickness reduction sometimes occurs locally in a portion of the processing container during the subsequent film-forming process. Through in-depth research, the inventors determined that this phenomenon arises because, at the time immediately following the cleaning treatment, the residual F concentration within the processing container is not uniform (non-uniform) throughout the container. Specifically, at the time immediately following the cleaning treatment, there exists a first section 211 with the highest residual F concentration and a second section 222 with a lower residual F concentration than the first section 211. Thus, even if the pre-coating treatment is performed under uniform processing conditions (uniform temperature distribution, etc.) throughout the entire processing container, and the residual F concentration in the second section 222 is relatively low, it is possible that the residual F concentration cannot be sufficiently reduced in the first section 211, where the residual F concentration is relatively high. If the subsequent film formation process is carried out in this state, even if the film thickness reduction can be prevented in the second step 222 where the residual F content can be sufficiently reduced, the film thickness reduction will occur locally in the first step 211 where the residual F content cannot be sufficiently reduced. As a result, the film thickness uniformity of the film formed on the wafer 200, especially the inter-wafer film thickness uniformity, may sometimes be reduced.

[0119] To address this issue, one approach could be to ensure a longer pre-coating time, forming a thicker pre-coating film over the entire area within the processing container, thereby sufficiently reducing residual F components not only in the second step 222 but also in the first step 211. However, this method sometimes results in longer downtime for the substrate processing apparatus, reducing the productivity of the semiconductor device. Furthermore, because the pre-coating film is formed too thickly over the entire area within the processing container, it can sometimes lead to an increase in the frequency of cleaning processes and an increase in the manufacturing cost of the semiconductor device.

[0120] Therefore, in the pre-coating process of this method, the film thickness distribution of the pre-coated film is adjusted according to the distribution of residual F concentration within the processing container. Preferably, in the pre-coating process, the pre-coated film formed in the first part 211, where the residual F concentration in the processing container is the highest, is thicker than the pre-coated film formed in the second part 222, where the residual F concentration in the processing container is lower than that in the first part 211. Hereinafter, the following will be mainly used. Figure 4 An example of the sequence in which a pre-coated film is formed in the processing container, i.e., a pre-coating sequence example, will be described. In the following description, the operation of each part constituting the substrate processing apparatus is also controlled by the controller 121.

[0121] In the pre-coating sequence of this method, pre-coating gas is supplied to the processing container after the pile of unaccounted wafers 200 has been removed, and a pre-coating film is formed inside the processing container.

[0122] The following describes examples of nitride films formed as pre-coated films. As mentioned above, nitride films include not only SiN films but also nitride films containing C, O, B, etc. That is, nitride films include SiN films, SiCN films, SiON films, SiOCN films, SiBCN films, SiBN films, SiBOCN films, SiBON films, etc. The following describes examples of SiN films formed as nitride films.

[0123] Furthermore, the following describes an example of performing a predetermined number of cycles (n times, where n is an integer greater than or equal to 1) in the pre-coating process. This cycle includes the steps of supplying a raw material gas into the processing container as a pre-coating gas and supplying a reactive gas into the processing container as a pre-coating gas. Alternatively, the steps of supplying the raw material gas and supplying the reactive gas can be performed alternately, i.e., not simultaneously, as shown in the processing sequence below. Alternatively, these steps can be performed simultaneously. Hereinafter, as an example, an example of performing these steps simultaneously, i.e., the latter processing sequence, will be described.

[0124] (Raw material gas → Reactant gas) × n

[0125] (raw material gas + reactant gas) × n

[0126] Additionally, the following uses Figure 3 An example of the methods in Part 111 and Part 222 will be explained. However, it should be noted that the method shown below is only one example. The areas within the processing container that can become Part 111 and Part 222 are determined by various factors such as the construction of the processing container, the cleaning process steps, and the processing conditions, and sometimes may differ from these factors. Figure 3 The methods shown are inconsistent.

[0127] As in this embodiment, when a region containing a heat insulation plate 216 is provided within the processing container, there may be a first part 211 including the region containing the heat insulation plate 216 within the processing container, and a second part 222 including the region within the processing container where the heat insulation plate 216 is not provided. Furthermore, as in this embodiment, when a region containing a wafer 200 and a region containing a heat insulation plate 216 are provided within the processing container, there may be a first part 211 including the region containing the heat insulation plate 216 within the processing container, and a second part 222 including the region containing the wafer 200 within the processing container. Figure 3 In the diagram, the heat insulation plate 216 is represented by a solid line, and the wafer 200 is represented by a dashed line. Furthermore, the area where the wafer 200 is disposed refers to the area within the processing container where the wafer 200 is disposed during the film deposition process.

[0128] Furthermore, as in this embodiment, when a region containing multiple heat insulation plates 216 is provided within the processing container, there may be a first part 211 including the region containing the multiple heat insulation plates 216 within the processing container, and a second part 222 including the region within the processing container where no multiple heat insulation plates 216 are arranged. Additionally, as in this embodiment, when a region containing multiple wafers 200 and a region containing multiple heat insulation plates 216 are provided within the processing container, there may be a first part 211 including the region containing the multiple heat insulation plates 216 within the processing container, and a second part 222 including the region containing the multiple wafers 200 within the processing container. Moreover, the region containing multiple wafers 200 refers to the region where multiple wafers 200 are arranged within the processing container during the film deposition process.

[0129] Furthermore, as in this method, when the processing container has a lower region, a central region, and an upper region, there may be a case where the first part 211 is the lower region within the processing container, and the second part 222 is at least one of the upper region and the central region within the processing container. Also, as in this method, when the processing container has a lower region and a region other than the lower region, there may be a case where the first part 211 is the lower region within the processing container, and the second part 222 is a region other than the lower region within the processing container.

[0130] Furthermore, as in this embodiment, when the processing container is provided with an upstream region, a midstream region, and a downstream region for the airflow, there is a case where the first part 211 is the upstream region for the airflow within the processing container, and the second part 222 is at least one of the downstream and midstream regions for the airflow within the processing container. Additionally, as in this embodiment, when the processing container is provided with an upstream region and regions other than the upstream region for the airflow, there is a case where the first part 211 is the upstream region for the airflow within the processing container, and the second part 222 is a region other than the upstream region for the airflow within the processing container. Moreover, in this embodiment, the gas flows from the lower region side to the upper region side within the processing container; therefore, the upstream, midstream, and downstream regions of the airflow correspond to the lower, central, and upper regions, respectively.

[0131] Furthermore, as in this embodiment, when the processing container has a substrate transfer port 209a for transferring the wafer 200 into the processing container, there may be a case where the first part 211 is the region on the side of the substrate transfer port 209a within the processing container, and the second part 222 is the region on the side of the processing container opposite to the side of the substrate transfer port 209a. Alternatively, there may be a case where the first part 211 is the region on the side of the substrate transfer port 209a within the processing container, and the second part 222 is the region other than the region on the side of the substrate transfer port 209a within the processing container.

[0132] Furthermore, one reason for including the aforementioned regions in Part 111 and Part 222 is the difference in gas conductance, i.e., flow resistance, within the processing container. As described above, cleaning is performed with an empty wafer boat 217, for example, a wafer boat 217 containing only the heat shield 216, housed within the processing container. Therefore, during the cleaning process, in the regions within the processing container where the heat shield 216 is arranged or positioned, the flow of F-containing gas is obstructed by the heat shield 216, and F-containing gas tends to stagnate and remain in these regions. In contrast, during the cleaning process, in the regions within the processing container where the wafer 200 is arranged or positioned during the film deposition process, since the wafer 200 is not present, the flow of F-containing gas is less likely to be obstructed, and F-containing gas stagnation and residue are less likely to occur. As a result, at the time immediately after the cleaning process, the first part 211 includes the area within the processing container where the heat insulation plate 216 is configured or arranged, and the second part 222 includes the area within the processing container where the heat insulation plate 216 is not configured or arranged (the area within the processing container where the wafer 200 is configured or arranged during the film formation process).

[0133] Furthermore, one reason why the first part 211 and the second part 222 include the aforementioned regions is the difference in the surface area of ​​the components capable of adsorbing F-containing gas within the processing container. As described above, the cleaning process is performed with an empty wafer boat 217, for example, a wafer boat 217 containing only the heat insulation plate 216, housed within the processing container. Therefore, during the cleaning process, in the regions within the processing container where the heat insulation plate 216 is arranged or positioned, the surface area of ​​the components capable of adsorbing F-containing gas becomes larger, and the amount of F-containing gas adsorbed increases. Conversely, during the cleaning process, in the regions within the processing container where the wafer 200 is arranged or positioned during the film-forming process, since the wafer 200 is not present, the surface area of ​​the components capable of adsorbing F-containing gas becomes smaller, and the amount of F-containing gas adsorbed decreases. As a result, the first part 211 includes the area within the processing container where the heat insulation plate 216 is configured or arranged, and the second part 222 includes the area within the processing container where the heat insulation plate 216 is not configured or arranged (the area within the processing container where the wafer 200 is configured or arranged during the film formation process).

[0134] Furthermore, one reason for including the aforementioned regions in Part 111 and Part 222 is the temperature distribution within the processing container. During the cleaning process, the region upstream of the airflow within the processing container (the region on the substrate conveying port 209a side) is at a lower temperature compared to at least one region on the downstream and midstream sides of the airflow within the processing container (regions other than the region on the upstream side of the airflow, and regions opposite to the region on the substrate conveying port 209a side), making it difficult for F-containing gases adsorbed on the component surface to detach from the component surface. Conversely, during the cleaning process, the region downstream and midstream of the airflow within the processing container (regions other than the region on the upstream side of the airflow, and regions opposite to the region on the substrate conveying port 209a side) is at a higher temperature compared to the region on the upstream side of the airflow within the processing container (the region on the substrate conveying port 209a side), making it easier for F-containing gases adsorbed on the component surface to detach from the component surface. As a result, the first part 211 includes the upstream region of the airflow in the processing container (the region on the substrate transport port 209a side), and the second part 222 includes at least one of the downstream and midstream regions of the airflow in the processing container (the region other than the region on the upstream side of the airflow, and the region on the opposite side of the region on the substrate transport port 209a side).

[0135] (Pressure adjustment and temperature adjustment)

[0136] After the cleaning process is completed, vacuum pump 246 is used to perform vacuum venting (pressure reduction venting) to bring the processing chamber 201 to the desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by pressure sensor 245, and the APC valve 242 is controlled based on this measured pressure information (pressure adjustment). Additionally, heater 206 is used to heat the processing chamber 201 to bring it to the desired processing temperature. To achieve the desired temperature distribution inside the processing chamber 201, the energization of heater 206, specifically the energization of each of the five regions (L, CL, C, CU, U) of heater 206, is independently controlled based on the temperature information detected by temperature sensor 263 (temperature adjustment). Furthermore, the empty wafer boat 217 is rotated using rotating mechanism 254. The operation of vacuum pump 246, heating of the processing chamber 201, and rotation of wafer boat 217 all continue at least until the cleaning process is completed. Alternatively, wafer boat 217 may not rotate.

[0137] (Pre-coating treatment)

[0138] Then, proceed with steps 3 and 4 in sequence.

[0139] [Step 3]

[0140] In step 3, raw material gas and reaction gas are simultaneously supplied as pre-coating gas into the processing chamber 201 that does not contain the wafer 200.

[0141] The specific processing steps can be the same as step 1 in the film-forming process described above. One or more of the raw material gases exemplified in the film-forming process can be used as the raw material gas. One or more of the reaction gases exemplified in the film-forming process can be used as the reaction gas. The raw material gas and reaction gas supplied to the processing chamber 201 rise within the processing chamber 201, flow out from the upper opening of the inner tube 204 into the cylindrical space 250, flow down into the cylindrical space 250, and are discharged from the exhaust pipe 231. During this process, the raw material gas and reaction gas mix, and the mixed raw material gas and reaction gas (pre-coating gas supply) are supplied to the surface of the components inside the processing container. At this time, valves 261c, 262c, 261d, and 262d can also be opened to supply inert gas into the processing chamber 201 via nozzles 230a and 230b, respectively.

[0142] As a processing condition in this step, the following examples are provided:

[0143] Processing temperature: 600~850℃, preferably 700~800℃

[0144] Processing pressure: 1~2666Pa, preferably 13~1333Pa

[0145] Feed gas supply flow rate: 0.01~2 slm, preferably 0.05~0.5 slm

[0146] Reactant gas supply flow rate: 0.1~10 slm, preferably 0.5~5 slm

[0147] Inert gas supply flow rate (per gas supply pipe): 0~5slm

[0148] Gas supply time: 1~120 minutes, preferably 1~60 minutes

[0149] Using a chlorosilane gas as the feed gas, for example, the aforementioned chlorosilane gas, and using a nitriding gas as the reactant gas, step 3 is performed under the aforementioned processing conditions. This process, via thermal CVD reaction, forms a silicon nitride layer (SiN layer) containing Si and N on the outermost surface of the components within the processing container. Furthermore, during this process, residual F components within the processing container are removed by reacting with the pre-coated gas and discharged from the processing container. Additionally, the components within the processing container include, for example, at least one of the following: processing tube 203, wafer boat 217, heat shield 216, manifold 209, rotating shaft 255, and sealing cap 219.

[0150] [Step 4]

[0151] After step 3 is completed, the processing chamber 201 is evacuated under the same processing steps and conditions as step 2 in the film formation process to remove any remaining gases from the processing chamber 201, thus purging the processing chamber 201. At this time, purging gas can also be supplied to the processing chamber 201 in the same manner as in step 2. As in step 2, the aforementioned reaction gas and inert gas can be used as the purging gas.

[0152] [Number of scheduled implementations]

[0153] By performing steps 3 and 4 of the above process a predetermined number of times (n times, where n is an integer greater than or equal to 1), a silicon nitride film (SiN film) of a desired thickness can be formed as a pre-coating film on the surface of the component inside the processing container. Preferably, by repeating the above process multiple times, and using gases containing N, C, and H as the reaction gases, a SiCN film can also be formed as a pre-coating film on the surface of the component inside the processing container, which is the same as the film formation process described above.

[0154] As described above, in the pre-coating process of this method, the film thickness distribution of the pre-coated film is adjusted according to the distribution of residual F concentration in the processing container after the cleaning process. Preferably, in the pre-coating process of this method, the pre-coated film of the first part 211, which has the highest residual F concentration in the processing container, is thicker than the pre-coated film of the second part 222, which has a lower residual F concentration in the processing container than the first part 211.

[0155] In this method, in order to achieve the above-mentioned film thickness distribution in the pre-coated film, it is preferable to independently adjust the energization of each of the five regions (L, CL, C, CU, U) of the heater 206, so that the temperature ratio of the first part 211 to the second part 222 in the pre-coated film treatment is greater than the temperature ratio of the first part 211 to the second part 222 in at least one of the above-mentioned film formation treatment (before cleaning) and the film formation treatment described later (after pre-coating film).

[0156] In addition, in order to achieve the above-mentioned film thickness distribution in the pre-coated film, it is preferable that, during the pre-coating process, the energization of each of the five regions (L, CL, C, CU, U) of the heater 206 is independently adjusted so that the temperature of the first part 211 is higher than the temperature of the second part 222.

[0157] In addition, in order to achieve the above-mentioned film thickness distribution in the pre-coated film, it is preferable to independently adjust the energization of each of the five regions (L, CL, C, CU, U) of the heater 206 so that the temperature of the first part 211 in the pre-coating process is higher than the temperature of the first part 211 in at least one of the above-mentioned film-forming process (before cleaning) and the film-forming process described later (after pre-coating).

[0158] (Post-purge and atmospheric pressure recovery)

[0159] After the pre-coated film is formed in the processing container, inert gas is supplied into the processing chamber 201 through nozzles 230a and 230b, and exhaust is performed through exhaust pipe 231. This purges the processing chamber 201, removing residual gases and byproducts (post-purge). Subsequently, the atmosphere in the processing chamber 201 is replaced with inert gas (inert gas replacement), and the pressure inside the processing chamber 201 is restored to atmospheric pressure (atmospheric pressure restoration).

[0160] (Unloading of empty wafer boat)

[0161] Next, the sealing cover 219 is lowered by the wafer boat lift 115, opening the lower end of the manifold 209. Then, the empty wafer boat 217 is moved out of the processing tube 203 through the lower end opening of the manifold 209 (substrate transfer port 209a) (wafer boat unloading). After the wafer boat is unloaded, the gate 219a is moved, and the lower end opening of the manifold 209 is sealed by the gate 219a via the O-ring 220c (gate closing).

[0162] (5) Film formation treatment (after pre-coating)

[0163] After the pre-coating process, the new wafer 200 undergoes the same film-forming process as described above (before cleaning). Specifically, a film-forming gas is supplied to the processing container holding the new wafer 200 after the pre-coating film has been formed, and the film is formed on the new wafer 200 again. The processing steps and conditions at this time can be the same as those in the film-forming process (before cleaning). One or more of the raw material gases exemplified in the film-forming process (before cleaning) can be used as the raw material gas. One or more of the reaction gases exemplified in the film-forming process (before cleaning) can be used as the reaction gas.

[0164] (6) The effect of this method

[0165] According to this method, one or more of the following effects can be obtained.

[0166] (a) In the pre-coating process, by adjusting the film thickness distribution of the pre-coated film to match the distribution of the residual F concentration within the processing container, it is possible to suppress the localized reaction between the residual F component and the film-forming gas within the processing container during the film-forming process (after pre-coating). Therefore, during the film-forming process (after pre-coating), it is possible to suppress the localized increase in the amount of film-forming gas consumed that does not contribute to film formation on wafer 200, and to suppress the occurrence of localized film thickness reduction.

[0167] (b) In the pre-coating process, by making the pre-coated film formed on the first part 211 thicker than the pre-coated film formed on the second part 222, it is possible to suppress the excessive reaction between residual F components and film-forming gas in the part of the processing container where the residual F concentration is highest during the film-forming process (after pre-coating). As a result, during the film-forming process (after pre-coating), it is possible to suppress the local increase in the amount of film-forming gas consumed that does not contribute to the formation of a film on the wafer 200 in that part, and it is possible to suppress the excessive local occurrence of film thickness reduction in that part.

[0168] (c) By making the ratio of the temperature of the first part 211 to the temperature of the second part 222 in the pre-coating process greater than the ratio of the temperature of the first part 211 to the temperature of the second part 222 in at least one of the film-forming process (before cleaning) and the film-forming process (after pre-coating), it is easy to make the pre-coated film formed in the first part 211 thicker than the pre-coated film formed in the second part 222 in the pre-coating process.

[0169] (d) In the pre-coating process, by making the temperature of the first part 211 higher than that of the second part 222, the pre-coating film formed on the first part 211 can be made thicker than the pre-coating film formed on the second part 222.

[0170] (e) By making the temperature of the first part 211 in the pre-coating process higher than the temperature of the first part 211 in the film-forming process (before cleaning), it is easy to make the pre-coated film formed in the first part 211 thicker than the pre-coated film formed in the second part 222 in the pre-coating process.

[0171] (f) For use in Part 1 211 and Part 2 222 Figure 3 In the cases illustrated above, one or more of the effects described above can also be obtained.

[0172] (g) When the above-mentioned raw material gas and reactant gas are used in the film-forming process (before cleaning, after pre-coating), when the above-mentioned raw material gas and reactant gas are used in the pre-coating process, when the above-mentioned F-containing gas is used in the cleaning process, and when the above-mentioned inert gas is used in these processes, the above-mentioned effects can also be obtained.

[0173] (7) Variations

[0174] The various processes in this method can be modified as shown in the following variations. In these variations, the same effect as the method described above can be obtained. Furthermore, these variations can be combined arbitrarily. Unless otherwise specified, the processing steps and conditions in each step of each variation can be the same as the processing steps and conditions in each step of the processes described above.

[0175] (Variation Example 1)

[0176] In the film formation process (before cleaning), the temperature of the first part 211 can be set below the temperature of the second part 222. According to this modified example, in the film formation process (before cleaning), the film thickness uniformity of the film formed on the wafer 200, especially the inter-wafer film thickness uniformity, can be improved. Furthermore, by making the temperature of the first part 211 lower than the temperature of the second part 222 in the film formation process (before cleaning), the effects described herein can be further improved.

[0177] (Variation Example 2)

[0178] In the cleaning process, the temperature of the first part 211 can be set below the temperature of the second part 222. According to this modified example, in the cleaning process, deposits containing membranes adhering to the processing container can be removed uniformly. Furthermore, by making the temperature of the first part 211 lower than the temperature of the second part 222 in the cleaning process, the effects described herein can be further improved.

[0179] (Variation Example 3)

[0180] In the film formation process (after pre-coating), the temperature of the first part 211 can be lower than the temperature of the second part 222. According to this modified example, in the film formation process (after pre-coating), the film thickness uniformity of the film formed on the wafer 200, especially the inter-wafer film thickness uniformity, can be improved. Furthermore, in the film formation process (after pre-coating), by making the temperature of the first part 211 lower than the temperature of the second part 222, the effects described herein can be further improved.

[0181] <Other methods of this disclosure>

[0182] The foregoing has detailed the manner in which this disclosure is made. However, this disclosure is not limited to the manner described above, and various modifications can be made without departing from its spirit.

[0183] For example, as reactant gases, in addition to the aforementioned gases containing N and H, and gases containing N, C, and H, examples include carbon (C) gases such as ethylene (C2H4), acetylene (C2H2), and propylene (C3H6), boron (B) gases such as diborane (B2H6) and trichloroborane (BCl3), oxygen (O2), ozone (O3), and O2 gas after plasma excitation (O2... * O2 gas + hydrogen (H2) gas, water vapor (H2O) gas, hydrogen peroxide (H2O2) gas, nitrous oxide (N2O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO2) gas, carbon monoxide (CO) gas, carbon dioxide (CO2) gas, and other oxygen-containing (O) gases.

[0184] Furthermore, by forming films containing Si, such as silicon oxynitride (SiON), silicon oxycarbide (SiOC), silicon oxycarbonide (SiOCN), silicon oxycarbonide (SiBCN), silicon boron oxynitride (SiBN), and silicon oxide (SiO), in addition to SiN and SiCN films, on the substrate using the film formation sequence shown below, the cleaning and pre-coating processes described above can also be appropriately applied. In these cases, at least some of the effects described in the above-described methods can be obtained. Moreover, the processing steps and conditions for supplying the raw material gas and reactant gas can, for example, be the same as the processing steps and conditions in each step of the above-described methods. In these cases, the same effects as in the above-described methods can also be obtained.

[0185] Furthermore, for example, when using a raw material gas containing metallic elements such as aluminum (Al), titanium (Ti), hafnium (Hf), zirconium (Zr), tantalum (Ta), molybdenum (Mo), and tungsten (W) to form films containing metallic elements such as aluminum nitride (AlN film), titanium nitride (TiN film), hafnium nitride (HfN film), zirconium nitride (ZrN film), tantalum nitride (TaN film), molybdenum nitride (MoN film), tungsten nitride (WN film), aluminum oxide (AlO film), titanium oxide (TiO film), hafnium oxide (HfO film), zirconium oxide (ZrO film), tantalum oxide (TaO film), molybdenum oxide (MoO film), tungsten oxide (WO film), silicon oxynitride (TiON film), titanium aluminum carbonitride (TiAlCN film), titanium aluminum carbide (TiAlC film), and titanium carbonitride (TiCN film) as raw material gases, the above-mentioned cleaning and pre-coating processes can also be appropriately applied. In these cases, at least some of the effects described in the above-described methods can also be obtained. Furthermore, the processing steps and conditions for supplying the raw material gas and reactant gas can, for example, be the same as the processing steps and conditions in each step of the above-described methods. In these cases, the same effects as those described in the above-described methods can also be obtained.

[0186] The processes used in each process are preferably prepared separately according to the processing content and pre-stored in the storage device 121c via electrical communication lines and external storage device 123. Furthermore, when starting each process, the CPU 121a preferably selects an appropriate process from the multiple processes stored in the storage device 121c according to the processing content. This allows for reproducible film deposition processes of various film types, composition ratios, film qualities, and film thicknesses, as well as cleaning and pre-coating processes corresponding to various films, using a single substrate processing device. In addition, it reduces the operator's workload, avoids operational errors, and allows for rapid initiation of each process.

[0187] The aforementioned process is not limited to the case of new manufacturing. For example, it can also be prepared by modifying an existing process already installed on the substrate processing apparatus. In the case of process modification, the modified process can also be installed on the substrate processing apparatus via an electrical communication line or a recording medium containing the process. Alternatively, the existing process already installed on the substrate processing apparatus can be directly modified by operating the input / output device 122 of the existing substrate processing apparatus.

[0188] In the above-described method, an example of performing film deposition, cleaning, and pre-coating processes using a batch-type substrate processing apparatus that processes multiple substrates at a time has been explained. This disclosure is not limited to the above-described method; for example, it can also be appropriately applied to cases where film deposition, cleaning, and pre-coating processes are performed using a single-sheet substrate processing apparatus that processes one or more substrates at a time. Furthermore, in the above-described method, an example of performing film deposition, cleaning, and pre-coating processes using a substrate processing apparatus with a hot-wall type furnace has been explained. This disclosure is not limited to the above-described method; it can also be appropriately applied to cases where film deposition, cleaning, and pre-coating processes are performed using a substrate processing apparatus with a cold-wall type furnace.

[0189] When using these substrate processing apparatuses, each processing step and processing condition can be performed in the same manner and under the same conditions as described above and in the modified examples, and the same effect as described above and in the modified examples can be obtained.

[0190] The methods and variations described above can be used in appropriate combinations. The processing steps and conditions can be set to be the same as those in the methods and variations described above.

[0191] Example

[0192] (Example 1)

[0193] use Figure 1 The substrate processing apparatus shown performs the film formation process, cleaning process, and pre-coating process described above. In the pre-coating process, the temperature of the lower region within the processing container is higher than the temperature of the upper and central regions within the processing container. The thickness of the pre-coated film is measured, and it is confirmed that the film thickness T1 of the pre-coated film formed in the lower region within the processing container is thicker than the film thickness T2 of the pre-coated film formed in the upper and central regions within the processing container. T1 is 1.2 to 1.4 times T2. After the pre-coating process, a film formation process is performed again within the processing container where the pre-coated film has been formed, and the film thickness of the film formed on the wafer is measured. Furthermore, in the film formation process, a SiN film is formed on the wafer, and in the pre-coating process, a SiN film is formed within the processing container as a pre-coating film.

[0194] (Comparative Example 1)

[0195] use Figure 1 The substrate processing apparatus shown performs the film formation and cleaning processes described above, and performs a pre-coating process under different processing conditions than in Example 1. In the pre-coating process, the temperature of the lower region within the processing container is lower than the temperature of the upper and central regions within the processing container. The thickness of the pre-coated film was measured, and it was confirmed that the film thickness T3 of the pre-coated film formed in the lower region within the processing container is thinner than the film thickness T4 of the pre-coated film formed in the upper and central regions within the processing container. T3 is 0.7 to 0.9 times T4. After the pre-coating process, a film formation process is performed again within the processing container where the pre-coated film has been formed, and the film thickness of the film formed on the wafer is measured. Furthermore, in the film formation process, a SiN film is formed on the wafer, and in the pre-coating process, a SiN film is formed within the processing container as a pre-coating film.

[0196] Furthermore, it was confirmed that the film thickness T1 of the pre-coated film formed in the lower region of the processing container in Example 1 was thicker than the film thickness T3 of the pre-coated film formed in the lower region of the processing container in Comparative Example 1. T1 was 1.4 to 1.6 times T3. Additionally, it was confirmed that the film thickness of the pre-coated films formed in the upper and central regions of the processing container in Example 1 was the same as the film thickness of the pre-coated films formed in the upper and central regions of the processing container in Comparative Example 1.

[0197] As a result, in Comparative Example 1, it was confirmed that during the film formation process after the pre-coating treatment, the film thickness formed on the wafer disposed in the lower region was thinner than the film thickness formed on the wafers disposed in the upper region and the central region, respectively. That is, in Comparative Example 1, it was confirmed that a reduction in film thickness occurred in the lower region.

[0198] In contrast, in Example 1, it was confirmed that during the film formation process after the pre-coating treatment, the film thicknesses formed on the wafers respectively disposed in the upper region, central region, and lower region were the same. That is, in Example 1, it was confirmed that no reduction in film thickness occurred in any of the upper region, central region, and lower region.

[0199] Symbol Explanation

[0200] 200 wafers (substrate)

[0201] Processing Room 201.

Claims

1. A substrate processing method, characterized in that, The processing method comprises the following steps: (a) A film-forming gas is supplied into a processing container containing a substrate to form a film on the substrate; (b) Supplying a fluorine-containing gas into the processing container that does not contain the substrate to remove deposits containing the membrane adhering to the processing container; (c) Supplying a pre-coating gas into the processing container after the removal of the deposits that do not contain the substrate, and forming a pre-coating film in the processing container; as well as (d) A film-forming gas is supplied to the processing container containing the substrate after the pre-coated film has been formed, thereby forming a film on the substrate. In (c), the film thickness distribution of the pre-coated film is adjusted in accordance with the distribution of residual fluorine concentration within the processing container.

2. The substrate processing method according to claim 1, characterized in that, In (c), the pre-coated film formed in the first part, where the residual fluoride concentration in the processing container is the highest, is thicker than the pre-coated film formed in the second part, where the residual fluoride concentration in the processing container is lower than that in the first part.

3. The substrate processing method according to claim 2, characterized in that, The ratio of the temperature of the first part to the temperature of the second part in (c) is greater than the ratio of the temperature of the first part to the temperature of the second part in at least one of (a) and (d).

4. The substrate processing method according to claim 2, characterized in that, In (c), the temperature of the first part is made higher than the temperature of the second part.

5. The substrate processing method according to claim 4, characterized in that, In (a), the temperature of the first part is lower than the temperature of the second part.

6. The substrate processing method according to claim 4, characterized in that, In (b), the temperature of the first part is lower than the temperature of the second part.

7. The substrate processing method according to claim 4, characterized in that, In (d), the temperature of the first part is lower than the temperature of the second part.

8. The substrate processing method according to claim 2, characterized in that, The temperature of the first part in (c) is higher than the temperature of the first part in at least one of (a) and (d).

9. The substrate processing method according to claim 2, characterized in that, An area with heat insulation panels is provided inside the processing container. The first part includes the area within the processing container where the heat insulation plate is configured. The second part includes the area within the processing container where the heat insulation plate is not configured.

10. The substrate processing method according to claim 2, characterized in that, The processing container includes an area for configuring a substrate and an area for configuring a heat insulation plate. The first part includes the area within the processing container where the heat insulation plate is configured. The second part includes the area within the processing container where the substrate is configured.

11. The substrate processing method according to claim 2, characterized in that, The processing container contains an area with multiple heat insulation panels arranged in a specific pattern. The first part includes the area within the processing container where the plurality of heat insulation panels are arranged. The second part includes the area within the processing container where the plurality of heat insulation plates are not arranged.

12. The substrate processing method according to claim 2, characterized in that, The processing container includes an area for arranging multiple substrates and an area for arranging multiple heat insulation plates. The first part includes the area within the processing container where the plurality of heat insulation panels are arranged. The second part includes the area within the processing container where the plurality of substrates are arranged.

13. The substrate processing method according to claim 2, characterized in that, The processing container is provided with a lower region, a central region, and an upper region, each with its temperature independently controllable. The first region is the lower region within the processing container, and the second region is at least one of the upper region and the central region within the processing container.

14. The substrate processing method according to claim 2, characterized in that, The processing container is provided with a lower region, a central region, and an upper region, each with its temperature independently controllable. The first region is the lower region within the processing container, and the second region is the region within the processing container other than the lower region.

15. The substrate processing method according to claim 2, characterized in that, The processing container is provided with a lower region (upstream side), a central region (midstream side), and an upper region (downstream side) that can be independently controlled in terms of temperature. The first region is the upstream side region of the airflow in the processing container, and the second region is at least one of the downstream side and the midstream side region of the airflow in the processing container.

16. The substrate processing method according to claim 2, characterized in that, The processing container is provided with a lower region (upstream side), a central region (midstream side), and an upper region (downstream side) where the temperature can be independently controlled. The first region is the upstream side region of the airflow in the processing container, and the second region is the region other than the upstream side region of the airflow in the processing container.

17. The substrate processing method according to claim 2, characterized in that, The processing container has a substrate delivery port for conveying substrates into the processing container. The first part is the region on the substrate transfer port side within the processing container, and the second part is the region on the opposite side of the substrate transfer port side within the processing container.

18. The substrate processing method according to claim 2, characterized in that, The processing container has a substrate delivery port for conveying substrates into the processing container. The first part is the area on the substrate transfer port side within the processing container, and the second part is the area outside the area on the substrate transfer port side within the processing container.

19. A method for manufacturing a semiconductor device, characterized in that, The manufacturing method comprises the following steps: (a) A film-forming gas is supplied into a processing container containing a substrate to form a film on the substrate; (b) Supplying a fluorine-containing gas into the processing container that does not contain the substrate to remove deposits containing the membrane adhering to the processing container; (c) Supplying a pre-coating gas into the processing container after the removal of the deposits that do not contain the substrate, and forming a pre-coating film in the processing container; as well as (d) A film-forming gas is supplied to the processing container containing the substrate after the pre-coated film has been formed, thereby forming a film on the substrate. In (c), the film thickness distribution of the pre-coated film is adjusted in accordance with the distribution of residual fluorine concentration within the processing container.

20. A substrate processing apparatus, characterized in that, have: A processing container that processes the substrate; A film-forming gas supply system that supplies film-forming gas into the processing container; A fluorine-containing gas supply system that supplies fluorine-containing gas into the processing container; A pre-coating gas supply system that supplies pre-coating gas into the processing container; A heater that heats the interior of the processing container; The control unit is configured to: (a) supply the film-forming gas into the processing container containing the substrate to form a film on the substrate; (b) supply the fluorine-containing gas into the processing container not containing the substrate to remove deposits containing the film adhering to the processing container; and (c) supply the pre-coating gas into the processing container after the deposits not containing the substrate have been removed to form a pre-coated film in the processing container. (d) supplying the film-forming gas into the processing container containing the substrate after the pre-coated film has been formed, and forming a film on the substrate, in (c) controlling the film-forming gas supply system, the fluorine-containing gas supply system, the pre-coated gas supply system, and the heater in a manner that corresponds to the distribution of the residual fluorine concentration in the processing container.

21. A computer-readable recording medium containing a program, characterized in that, The program uses a computer to cause the substrate processing device to perform the following steps: (a) A film-forming gas is supplied into a processing container containing a substrate to form a film on the substrate; (b) Supplying a fluorine-containing gas into the processing container that does not contain the substrate to remove deposits containing the membrane adhering to the processing container; (c) Supplying a pre-coating gas into the processing container after the removal of the deposits that do not contain the substrate, and forming a pre-coating film in the processing container; (d) Supplying the film-forming gas into the processing container housing the substrate after the pre-coated film has been formed, thereby forming a film on the substrate; and In (c), the film thickness distribution of the pre-coated film is adjusted in accordance with the distribution of residual fluorine concentration within the processing container.

Images